The invention concerns a lifting apparatus mounted suspendably to a holding apparatus. In operation, a pivotal angle of the lifting apparatus deviating from a vertical straight line can be limited by way of a safety apparatus, and such a lifting apparatus can be part of a crane and a vehicle having such a crane.
Such lifting apparatuses are already known from EP 2 433 898 A1. In that specification, the lifting apparatus involves for example a work cage which is mounted in gravitationally levelling relationship to a rotary mounting and can be blocked and damped by a hydraulic cylinder. The hydraulic cylinder is blocked by a blocking valve disposed in a compensating line between the two chambers C1 and C2 of the hydraulic cylinder. That valve is controlled by a controlling unit and enables or closes off the through-flow between the chambers C1 and C2 of the hydraulic cylinder. In addition, there is a throttle action between the two chambers and thus the swinging movement of the lifting apparatus is damped. That damping admittedly causes a slowing of the swinging movement of the lifting apparatus but it does not prevent the lifting apparatus inclining severely when the operator leans out. For that reason, the blocking valve is disposed in the compensating line between the chambers C1 and C2.
European Standard 280 requires that in precisely such a situation, the lifting apparatus may not incline further than 5° relative to the horizontal. If that 5° angle is exceeded, the swinging movement must be automatically stopped. Furthermore, the European Standard 280 requires that, if a lifting angle movement is nonetheless continued, which is performed for example by way of the lifting apparatus which is connected to the crane, a further inclination above 10° is automatically stopped at the lifting apparatus. The above-mentioned patent specification discloses that only one blocking valve is installed in the compensating line. That gives rise to the disadvantage that, at any inclination above 5° up to 10° the blocking valve is blocked by way of the controlling unit and no compensation can take place between the chambers C1 and C2 at the hydraulic cylinder. The operator therefore has to connect the two chambers together by means of deactivation of the safety apparatus in order to be able to horizontally orient the lifting apparatus.